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 A147597 a(n) is the number whose binary representation is A138146(n). 4
 1, 7, 31, 119, 455, 1799, 7175, 28679, 114695, 458759, 1835015, 7340039, 29360135, 117440519, 469762055, 1879048199, 7516192775, 30064771079, 120259084295, 481036337159, 1924145348615, 7696581394439, 30786325577735, 123145302310919, 492581209243655 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Bisection of A147596. LINKS Colin Barker, Table of n, a(n) for n = 1..1000 Index entries for linear recurrences with constant coefficients, signature (5,-4). FORMULA From R. J. Mathar, Feb 05 2010: (Start) a(n) = 5*a(n-1) - 4*a(n-2) for n>5. G.f.: x*(2*x+1)*(2*x-1)*(4*x^2+2*x+1)/((4*x-1)*(1-x)). (End) a(n) = 7*4^(n-2) + 7 for n>3. - Colin Barker, Nov 25 2016 MATHEMATICA Table[FromDigits[#, 2] &@ If[n < 4, ConstantArray[1, 2 n - 1], Join[#, ConstantArray[0, 2 n - 7], #]] &@ ConstantArray[1, 3], {n, 25}] (* or *) Rest@ CoefficientList[Series[x (2 x + 1) (2 x - 1) (4 x^2 + 2 x + 1)/((4 x - 1) (1 - x)), {x, 0, 25}], x] (* Michael De Vlieger, Nov 25 2016 *) PROG (PARI) Vec(x*(2*x+1)*(2*x-1)*(4*x^2+2*x+1)/((4*x-1)*(1-x)) + O(x^30)) \\ Colin Barker, Nov 25 2016 CROSSREFS Cf. A138146, A145641, A147537, A147538, A147539, A147540, A147590, A147595, A147596. Sequence in context: A091344 A032197 A114289 * A048775 A181951 A218963 Adjacent sequences:  A147594 A147595 A147596 * A147598 A147599 A147600 KEYWORD base,easy,nonn AUTHOR Omar E. Pol, Nov 08 2008 EXTENSIONS More terms from R. J. Mathar, Feb 05 2010 STATUS approved

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Last modified February 16 04:34 EST 2019. Contains 320140 sequences. (Running on oeis4.)